Meng-jie Jiang¹, Jian-fei Fu², Yi-nuo Tan³, Jiao Yang³, Lun-po Wu³, Lin Feng⁴, Shu Zheng³, Ying Yuan³

¹Department of Medical Oncology, The Second Affiliated Hospital, Zhejiang University School of Medicine, ²Department of Oncology, Jinhua Central Hospital (Jinhua Hospital of Zhejiang University School of Medicine), ³Zhejiang University School of Medicine, The Second Affiliated Hospital, ⁴Cancer Institute & Hospital, Department of Aetiology and Carcinogenesis

Objective:To evaluate the value of lymph node status of primary tumors in predicting the prognosis of synchronous resectable metastatic colorectal cancer (mCRC). Method: The data of 2007 patients with mCRC who received resection of the primary tumors and metastatic lesions synchronously were reviewed from the SEER database. The Kaplan-Meier method was used to evaluate the capacity of different prognostic factors. Univariate and multivariate logistic regression models were used to evaluate the relationship between the lymph node status and other factors. The mRNA profiles of primary resectable mCRC tumors were obtained by microarray at our center. Result: The median survival times were 50 months, 36 months, 32 months, 27 months and 19months in the N0-stage, N1a-stage, N1b-stage, N2a-stage and N2b-stage subgroups according to the 7th AJCC TNM N-classification (P=0.000), and 40 months, 29 months, 22 months and 15 months inpatients with metastatic lymph node ratio (LNR) (P=0.000). In the COX model, the 7th AJCC TNMN-stage and LNR were independent prognostic factors. The mRNA profile was not associated with lymph node involvement. Conclusion: Both the N-stage according to the 7th AJCCTNM staging system and LNR had the capacity to sub-classify synchronous resectable mCRC with different prognoses. The lymph node might be integrated into the AJCC staging system as a diagnose-delay prognostic factor for stage IV disease.

Key Words: resectable metastatic colorectal cancer (mCRC)  SEE